1. Field of the Invention
This invention relates to a production method of an ultrasonic weld assembly to which ultrasonic welding for welding work, by using ultrasonic oscillation, is applied.
2. Description of the Related Art
Japanese Unexamined Patent Publications Nos. 2003-80378, 2001-246479 and 11-77337, for example, have proposed ultrasonic welding methods in the past. According to such ultrasonic welding methods, an oscillator is made to oscillate, by a high frequency voltage, while a first member is pressed to a second member. Oscillations from the oscillator or a resonance horn connected to the oscillator causes oscillation of the first member or the second member and heat of friction generating at their contact surface weld them together. Consequently, a pipe as the first member and a pipe connection member as the second member, for example, can be hermetically welded.
However, these ultrasonic welding methods do not at all clarify the condition of ultrasonic welding required for conducting air-tight welding. Therefore, insufficient air-tight welding may occur in some cases by merely conducting the ultrasonic welding methods disclosed in these patent documents.